1. Field of Invention
This invention generally relates to the steering of boats, specifically to an improved mechanical device that allows a single-handed pilot to quickly and easily restrain the position of the tiller and rudder at the stern of a boat.
2. Prior Art
Most smaller boats, especially sailboats, are steered with a rudder at the stern that is pivoted by a long arm called a tiller. The tiller extends into the steering area, or cockpit, for the sailor or pilot to use.
When steering a boat single handedly, a sailor often needs to momentarily release the tiller to attend to other critical tasks, including changing sails, adjusting lines, preparing anchors, and retrieving needed articles from elsewhere on the boat. Without some method of restricting tiller movement, the rudder can quickly swing to one side or the other, causing the boat to veer off course with undesirable results. Conversely, with the tiller fixed in position, the boat may remain on course long enough for the sailor to complete a necessary task.
Sailors have addressed this problem in the past with varying degrees of success. Numerous solutions have been tried, ranging from elaborately-tied ropes or elastic cords to rods and clamps. A few simple cord-based devices have been patented as shown by U.S. Pat. No. 4,480,572 to Lauterbach (1984) and U.S. Pat. No. 5,335,616 to Tiesler (1994). The difficulty with these devices is that they occupy two hands for set-up or adjustment, and they cannot be released quickly or intuitively when necessary. Unfortunately, in windy, foul-weather or crowded conditions the ability to make a quick-steering adjustment can be crucial.
A number of rigid tiller restraining designs have been disclosed in U.S. Pat. No. 2,846,896 to Allen (1958), U.S. Pat. No. 3,279,410 to Young (1966), U.S. Pat. No. 4,178,869 to Turrentine (1979), U.S. Pat. No. 4,188,904 to Childress (1980), U.S. Pat. No. 4,476,800 to Gage (1984), U.S. Pat. No. 5,052,321 to Toniatti (1991), and U.S. Pat. No. 5,133,274 to Grant (1992). These devices employ a rod or wooden stick with one end mounted to a side of the boat and the other end adjustably attached to the tiller to hold it in position. Though somewhat effective, each of these contraptions would prove cumbersome and awkward to use within the crowded confines of smaller-sized boats that typically use tillers for steering. In particular, they can obstruct the use of several important ropes that require frequent monitoring within the cockpit. Additionally, when not in use, these awkward devices consume precious cockpit storage space, and they present an unsightly, incongruent effect on the neat lines of a sailing craft.
The more practical tiller control solutions employ a more compact mechanical device that is attached to the tiller and engages a small control rope strung across the steering area. The control rope is positioned so that the tiller glides along it when steering. The device restricts tiller movement by gripping the control rope at any chosen location along the arc of the tiller. Several such devices have been developed by others, but each has its shortcomings.
The majority of these products employ a tensioning spring-and-screw combination that applies friction directly to the control rope as it winds its way through the device. A few versions of similar design appear to be in the public domain including the Tiller-Tamer™ by Davis Instruments Corp (www.davisnet.com). Such a device can be useful, but has several disadvantages. First, it takes time to activate, as the knob must be rotated several turns to engage or disengage the control rope. For unrestricted steering, the user must fully unscrew the knob, thereby loosing any desired friction on the control rope. Often frustrated by this operational requirement, the user tends to leave the knob partially tightened and simply overpowers it for every steering adjustment. This use tends to wear on the control rope and allow the device to slip under normal water pressures acting upon the rudder. Even with the screw fully loosened, significant friction remains on the control rope as it rounds the three bends required by the tensioning apparatus. This friction detracts from the pleasurable feel of freely steering the boat. It also masks the natural feedback that the sailor feels from rudder pressures. This feedback is important for the sailor when trimming sails for varying conditions. Furthermore, the tensioning knob protrudes from the top of the device, where it has been known to dangerously snag critical ropes during quick sailing maneuvers.
To address some of these issues, U.S. Pat. No. 4,080,918 to Bonhard (1978) shows a device which uses a hinged clamp to grip the control rope as it passes directly through it. This improved simple mechanism allows for faster engaging and complete releasing of the control rope, and it retains a pre-determined rope friction when disengaged. However, this product also falls short. The pilot must use one hand to engage it, while using the other hand to steer. Therefore, two hands and visual attention are required when attempting quick steering adjustments. This requirement can detract from the pilot's focus on boat direction, sails, etc. at a time when all are impacted by the steering action taken. Additionally, when disengaged, the hinged clamp part swings awkwardly away from the tiller, where it can snag the main sheet rope as with the previously mentioned device. This extended part can present a scraping hazard to the user, and can badly pinch a finger when closed in a hurry.
U.S. Pat. No. 4,241,684 to Davis (1980) discloses a device that addresses some of these issues in a unique, though problematic way. This device employs a set of opposing friction-operated cams to engage the control rope. One of the cams can tighten on the control rope in opposition to rope tension from the other side. The other cam performs the reverse action, so that the rope is restrained in both directions. A remotely located bicycle brake-type lever is provided with a cable to release the cams and free the control rope. Conceptually, this appears to be an improvement, since little effort is needed to engage the rope and the rope cannot slip from increased pressure on the tiller. However, in practice, this increasing grip could be hazardous because the cams would not yield to excessive rudder forces that could cause rudder failure. Likewise, a pilot could not overpower the device in an emergency. Furthermore, increasing tension on the control rope would make the cams increasingly difficult for the lever to disengage. To counter this release problem, the pilot would have to carefully offset any significant rudder load on the tiller before using the release lever. This requirement would diminish the convenience of the device and could slow steering reaction time. Finally, installation of the product onto the tiller is complicated by the attachment of the two separate components that require careful alignment for proper operation.
Other previous mechanical tiller restraining devices were not included in this discussion, but each of them attempts to provide a useful means of restraining the tiller while it is momentarily unattended. Nevertheless, each previous device fails to provide a fully satisfactory solution with regard to efficiency, convenience and safety, having several of the following disadvantages:
(a) Both hands are occupied to operate the device while steering.
(b) The operator must focus attention on the device to locate it and to operate it effectively.
(c) The device does not lend itself to one-handed, minor steering corrections while in use.
(d) Working the device requires repeated or complex hand motions to rotate an adjustment knob or work a clamp.
(e) The device restrains the tiller too securely, so the tiller cannot be forced by hand pressure, and will not yield to excessive underwater rudder pressure.
(f) An upwardly-protruding part of the device can entangle operating lines on the boat, and can present a hazard to the user.
(g) Residual friction in the control rope effects steering feel when the device is disengaged.
(h) Rigid poles or rods of the device are cumbersome and consume limited storage space when not in use.
(i) The mechanism presents a pinching hazard to the user.
(j) The device is ungainly and unpleasing to the eye.
Some of these disadvantages represent inconveniences, while others can slow reaction time and hinder boat operation, or become hazardous in rough conditions.
3. Objects and Advantages
Accordingly, several objects and advantages of the present invention are:
(a) To provide a tiller restraining device that is integrated into the normal steering position for one-handed operation, so that the pilot can grip the tiller handle and simultaneously restrict or un-restrict tiller movement;
(b) To provide a tiller restraining device that is intuitive in use, not requiring extra thought or wasted motion;
(c) To provide a tiller restraining device that allows one-handed, momentary release the for minor steering corrections;
(d) To provide a tiller restraining device that will instantly engage or release the control rope with a small motion of the fingers, even under load;
(e) To provide a tiller restraining device that can be predictably overpowered for emergencies, yet will not slip under normal working loads;
(f) To provide a tiller restraining device with a low profile that is secured beneath the tiller without upwardly protruding parts that could otherwise snag important sailboat lines, or cause a safety hazard;
(g) To provide a tiller restraining device that allows nearly frictionless steering when disengaged;
(h) To provide a tiller restraining device that is compact and can be permanently installed without taking up valuable space during use or storage;
(i) To provide a tiller restraining device that will not pinch the user's hand with normal use.
(j) To provide a tiller restraining device that is unobtrusive and aesthetically pleasing.
Further objects and advantages will become apparent from a consideration of subsequent description and drawings.